Identify Identities with pi & Theta: Precalculus Help

Thread starter Rosita
Start date Apr 18, 2009
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identities

AI Thread Summary

To represent pi and theta in equations, use the symbols π and θ respectively. The problem involves the identity sin(π/2 + θ) = cos(θ), which can be solved using the sine addition formula. This formula states that sin(A + B) = sin(A)cos(B) + cos(A)sin(B). For A = π/2 and B = θ, the identity simplifies to cos(θ), confirming the relationship. Understanding these identities is crucial for solving precalculus problems effectively.

Apr 18, 2009

Rosita

Homework Statement

How do I put the sign for pi and the sign for theta? I can not solve this problem.
Please help because I am new and I am having difficulty in my precalculus homework. The problem says identify identities of: sin (pi/2 + theta) = cos theta

Homework Equations

The Attempt at a Solution

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Apr 18, 2009

rock.freak667

Homework Helper

Do you know how to expand sin(A+B) ?

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